Refrigerating apparatus



Patented Nov. 22, 1932 BURT H. WESTON, OF WOOD RIVER, ILI-IDTOIS Innrnrqnnnrme arranarus Q Application filed latch 20, 1929. Serial No.348,834.

This invention relates to refrigerating apparatus and is designed moreparticularly for use with solid carbon dioxid as the refrigeratingmedium.

Carbon dioxid gas has an extremely low temperature and unless properlycontrolled will freeze or otherwise injuriously afiect substances, suchas food, within therefrigerator. While the gas is not poisonous it will,if brought into direct contact with foods, modify the taste thereof inan objectionable manner and it is therefore important that the gasshould not enter the food compartment.

One object of the invention is to provide a simple and eflicient meansfor utilizing solid carbon dioxid as a refrigerant and for controllingthe application or distribution of the gases given oil thereby in such amanner as to maintain the desired temperature in the compartment to becooled. A further object of the invention is to provide such anapparatus having means for automatically controlling the application ofthe carbon dioxid gas to the compartment.

to be cooled in accordance with the tempera.- ture in said compartment.

A further object of the invention is to provide such an apparatus'having means for predetermining the temperature which is to bemaintained in the compartment to be cooled. s

A further object of the invention is to provide such an apparatus withmeans for preventing or retardin the evaporation or sublimation of thesoli carbon dioxid when the compartment to be cooled is at the desiredtemperature.

A further object of the invention is to provide in such an apparatus acirculation system for carbon dioxid gas which will be independent ofthestructure in which the compartment to be cooled is located, thusavoiding the breaking of joints or leakage which frequently results whenthe circulation channels are built into the structure itself, especiallywhen said structure is embodied in a refrigerator car or truck. I Afurther object of the invention is to provide a circulation system ofsuch a character that the carbon dioxid gas may be caused to circulatetherethrough, and the circulation controlled, without the use of pumpsor other mechanical devices.

Other objects of the invention will appear as the apparatus'is describedin detail.

In the accompanying drawing Fig. 1 is a top plan view, partly insection, of a refrigerating apparatus embodying my invention; Fig. 2 isa longitudinal vertical section taken through such an apparatus; andFig.

3 isa detail view of the regulating valve.

In the drawing I have illustrated one embodiment of my invention andhave shown thesame as applied to a refrigerator truck but it will beunderstood that this particular embodiment has been chosen for thepurposes of illustration only and that the a paratus may take variousforms and may applied to refrigerators of various kinds, eitherstationary or portable, without departing from the spirit of theinvention.

In that embodiment of the invention here illustrated the refrigerator ismounted on and forms the body of a truck and comprises a main bodyportion or structure) 5 having a lining 6 of insulating material, withinwhich is formed the compartment to be cooled, 7. The body structure isprovided in one side thereof with doors 8 to permit access thereto.Mounted adjacent to, and preferably above, the top of the compartment 7is a refrigerant chamber 9 adapted to receive blocks or cakes of solidcarbon dioxid, as shown at 10. This refrigerant chamber has a removabletop 'wall 'or' closure 11 to permit access thereto and the closure is ofsuch a character as to tightly seal the chamber when in closingposition. The refrigerant chamber is wholly separate from the com-'partment 7 and is insulated both from that compartment and from theatmosphere.

The carbon dioxid gas given off by the blocks of solid carbon dioxid inthe refrigerant chamber may be circulated or distributed in coolingrelation to the compartment 7 which is to be cooled, in any suitablemanner but I prefer to utilize a. cooling element which is constructedseparately from I the body structure of the apparatus. This coolingelement is located in such relation to the chamber 7 that the carbondioxid gas in the cooling element will absorb heat from the chamber tobe cooled, and preferably it is located near the top of that chamber.The present apparatus comprises a relatively long body'portion and Ihave therefor 10-- cated the refrigerant chamber substantially midwaybetween the ends of that structure and have provided two separatecooling elements, one arranged in each end portion of the bodystructure. It will be understood, however, that the number of coolingelements employed in any given installation will depend to a largeextent upon the size and character of the chamber to be cooled.

The two cooling elements are here shown as mounted in the upper part ofthe chamber to be cooled and below the level of the lowest part of therefrigerant chamber. Each cooling element comprises two manifolds, 12and 13, spaced apart, the manifold 12 being preferably located directlybeneath the refrigerant chamber and the manifold 13 being arranged nearthe end of the compartment to be cooled. The two manifolds" areconnected one with the other by a plurality of conduits or pipes 14which are spaced apart across substantially thefull width of thecompartment to be cooled. The manifold 12 is connected with therefrigerant chamber 9 by a pipe or conduit 15 which opens into the lowerpart of the refrigerant chamber so that the carbon dioxid gas given offby the block of solid carbon dioxid, and which is heavier than air, willmove by gravity through the conduit 15 into the manifold 12. Anysuitable number of conduits may be interposed between the manifold andthe refrigerant chamber and, in the present instance, I have shown two.The manifold 13 is provided with a suitable outlet for the gas so thatthe gas which passes from the refrigerant chamber to the manifold 12 maypass through the conduit or passageways 14 to the manifold 13 and thenceto the atmosphere or to a suitable recovery receptacle.

The flow of carbon dioxid gas through the cooling element should becontrolled or retarded so as to retain it in the cooling element untilit has absorbed as much heat as is practical in the operation of thedevice, thus reducing the temperature within the compartment to becooled. It is also desirable that means should be provided for retardingor preventing the evaporation or sublimination. of solid carbon dioxidin the refrigerant chamber when the temperature within the compartmentto be cooled has been reduced to the desired extent, thus avoiding thewaste of the carbon dioxid. Both functions are accomplished by providingthe manifold 13 with an outlet conduit having automatically controlledmeans for regulating the flow of gas through the cooling element. Carbondioxid gas has a specific gravity greater than that of air and I preferto control the flow of the gas by providing the outlet conduit with atrap which will prevent the passage of the gas untilits specific gravityhas, by the absorption of heat,

been raised to substantially that of the atmosphere. As here shown, theoutlet conduit comprises a portion 16 extending downwardly from themanifold 13, within the compartment to be cooled and to a point near thebottom of that compartment. From this lowest point the conduit extendsupwardly, as shown at 17, outside of the compartment to be cooled, andhas its discharge end near theto of that compartment. The upwardly extening part of the conduit is preferably insulated both from thecompartment to be cooled and from the atmosphere, so as to provide aneutral column of air or heat laden gas. It is preferable that the gasshould be discharged from the outlet conduit near the highest point fromwhich gas is delivered to the cooling element and I have thereforearranged the discharge opening of the outlet conduit near the top of therefrigerant chamber. In the present instance, the part 17 of the outletconduit is arranged within the insulating lining 6 of the body structureand extends through the end and top portions of that lining to the wallof the refrigerant chamber and thence upwardly to the atmosphere, asshown at 18.

When the apparatus is placed in operation the cooling element and theoutlet conduit will contain air at atmospheric ressure. The car bondioxid gas will pass rom the refrigerant chamber 9, and through theconduits 15 to the cooling element and through the several passagewaysin the cooling element to the outlet conduit, and because 'of itsspecific gravity will move downwardly to the lowest point of the outetconduit, dispacing the air as it advances. So long as the carbon dioxidgas retains its normal specific gravity it will not pass upwardlythrough the part 17 of the outletconduit but as it absorbs heat from thecompartment to be cooled its specific gravity will be gradually raiseduntil it can overcome the pressure 'of the air in the part 17 of theoutlet conduit, and this heat laden gas will then move upwardy throughthe conduit and will be discharged at the point 18, therebypermitting'of the flow of carbon dioxid gas through thecoolingelementand gradually lowering the temperature within the compartment to becooled until the gas in the heating element will no longer absorbsuflicient heat therefrom to permit it to rise through the upwardlyextending part of the outlet conduit. When this takes place the.

flow of gas through the cooling element is interrupted or retarded. Inpractice it is probable that there-would not be complete interruption ofthe flow of gas but that the gas would gradually absorb heat and moveslowly through the outlet conduit. By thus interrupting or retarding theflow of gas through the cooling element the temperature Within thecompartment to be cooled will be maintained at approximately apredetermined temperature. The temperature at which the compartment tobe cooled is maintained may be predetermined in any suitable manner butpreferably this is accomplished y providing the conduit or conduits withcontrolling devices to regulate the flow of gas through the same. In thepresent instance, this regulating device is in the form of a slide valve19, as shown in detail in Fig. 3, and comprises a slidable plate havinga series of openings 21 of diflerent diameters,

' any one of which may be moved into line with the conduit 15.1,The'quantity of gas which may pass from the refrigerant chamber to thecooling element is, of course, dependent upon the size of the orificeint-he plate 20 which is in line with the conduit 15, and the greaterthe quantity of gas which passes to the cooling element the greater thecooling action. When the flow of gas through the cooling element isinterrupted or is very slow the solid carbon dioxid in the refrigerantchamber will be completely surrounded by carbon dioxid gas whichinsulates the same and prevents the evaporation or sublimation thereof.Consequently the carbon dioxid is conserved and there is no wastethereof, as the solid carbon dioxid will evaporate only when the gas isflowing from the refrigerant chamber through the cooling element.

' By means of the very simple apparatus here illustrated and described Iam able to maintain in the compartment to be cooled a substantiallyuniform temperature of a predetermined degree, the flow of carbon dioxidgas through the cooling element being automatically controlled accordingto the temperature within the compartment, and by ad- ]usting thecontrolling valve 19 the degree of temperature which is maintained inthe compartment to be cooled may be determined. The circulation systemfor the gas is constructed wholly independently of the body structure ofthe apparatus and is of such a character that it is not liable to leak,due to the breaking of joints or otherwise. The

upwardlv extending portion of the outlet conduit is insulated byembedding the same in the insulating lining of the body structure, whichcan be easily accomplished after the body structure has been built.

While I have shown and described one embodiment of my invention I wishit to be understood that I do not desire to be limited to the detailsthereof as various modifications may occur to a person skilled in theart.

Having now fully described my invention,- what I claim as new and'desireto secure by Letters Patents, is:

1. In a refrigerating apparatus comprising a structure having acompartment to be cooled and having a. refrigerant chamber adapted toreceive solid carbon dioxid, means for conducting carbon dioxid gas fromsaid refrigerant chamber, in cooling relation to said compartment, to apoint spaced below the top of said compartment and thence upwardly to apoint of discharge, and means for insulating the upwardly extending partof said conducting means. i

2. In a refrigerating apparatus comprising I a structure having acompartment to be cooled and having a refrigerant chamber adapted toreceive solid carbon dioxid, a cooling element arranged in the upperpart of said compartment and having a passageway for car bon dioxidgasconnected with said refrigerant chamber, and an outlet conduitconnected with said passageway and extending downwardly within saidcompartment to a point near the bottom thereof and then upwardly andexteriorly of said compartment-and having a discharge opening near thetop of said refrigerant chamber. v

3. In a refrigerating apparatus COIHPI'iSilig a structure having acompartment to be cooled and having a refrigerant chamber near the topof said compartment and adapted to receive solid carbon dioxid, acooling element supported within said compartment below said refrigerantchamber and having a passageway for carbon dioxid gas connected withsaid refrigerant chamber, and an outlet conduit leading downwardly fromsaid passageway and then upwardly. p

4. In a refrigerating apparatus compr sing a structure having acompartment to be coole and having a refrigerant chamberne top of saidcompartment and'adapt ceive solid carbon dioxid, a'cool'ing lementsupported within said compartm said refrigerant chamber and havangafj'assageway for carbon dioxid gas connected with saidrefrigerant'chamber, and an outlet conduit leading downwardly from saidpascompartment and then upwardly to a point above said compartment. v 5.In a refrigerating apparatus comprlsmg a structure having a compartmentto be cooled I sageway to a point near the bottom of said and having arefrigerant chamber near the top of said compartment and adapted toreceive solid carbon di'oxid, a cooling element supported within saidcompartment below said refrigerant chamber and having a passageway forcarbon dioxid gas connected with said refrigerant chamber, and an outletconduit leading downwardly from said pasing a structure having acompartment to be cooled and having a refrigerant chamber near the topof said compartment and adapt-' ed to receive solid carbon dioxid, acooling element arranged near the top of said com-- partment and belowsaid refrigerant cham- ;ber and having a passageway for carbon dioxidgas connected with said refrigerant chamber, and an outlet conduit forsaid passageway shaped to form a trap which will prevent ,the passage ofcarbon dioxid gas until the specific gravity of said gas has. beenraised by the absorption of heat. I

'7. In a refrigerating apparatus comprising a structure having acompartment to be cooled and having a refrigerant chamber near the topof said compartment and adapted to receive solid carbon dioxid, acooling element arranged near the top of said compartment and below saidrefrigerant chamber and comprising a plurality of passageways connectedwith said refrigerant chainber, and an outlet conduit connected withsaid passageways and extending downwardly therefrom and then upwardly.

8. In a refrigerating apparatus comprising a structure having acompartment to be cooled and having a refrigerant chamber adapted toreceive solid carbon dioxid, a cooling element for said compartmenthaving a passageway for carbon dioxid gas connected with saidrefrigerant chamber, means for regulating the flow of carbon dioxid gasfrom said refrigerant chamber to said cooling element, and means forcontrolling the flow of carbon dioxid gas through said cooling elementin accordance with the temperature in said compartment.

9. In a refrigerating apparatus comprising a structure having acompartment to be and shaped to form a trapwhich will retard the vflowof carbon dioxid gas therethrough.

10. In a refrigerating apparatus comprising a structure having acompartment to be cooled and a refrigerant chamber arranged above saidcompartment and adapted to receive solid carbon dioxid, a coolingelement arranged within and near the top of said compartment andcomprising spaced manifolds and conduits connecting said manifolds onewith the other, means for connecting one of said manifolds with saidrefrigerant chamber to permit carbon dioxid gas to flow partment, andmeans for insulating the up- I wardly extending part of said outletconduit.

11. In a refrigerating apparatus comprising a structure having acompartment to be cooled and a refrigerant chamber arranged above saidcompartment and adapted to receive solid carbon dioxid, a coolingelement arranged within and near the top of said compartment andcomprising spaced manifolds and conduits connecting said manifolds onewith the other, means for connecting one of said manifolds with saidrefrigerant chamber to permit carbon dipxid gas to flow, from saidrefrigerant chamber to said cooling element, a valve to control saidconnection, an outlet conduit connected with the other of saidmanifolds, extending downwardly therefrom to a po1nt near the bottom ofsaid compartment and then extending upwardly to a point near the. top ofsaid compartment.

12. In a refrigerating apparatus, a structure having a compartment to becooledand a refrigerant chamber arranged above said compartment andbetween the ends thereof and adapted'to receive solid carbon dioxid,separate cooling elements arranged within said compartment on oppositesides of said refrigerant chamber, means for connecting the respectivecoolingl devices with said refrigerant chamber, eac of said coolingdevices comprising passageways through which said carbon dioxid gas mayflow, and outlet conduits connected with the passageways of therespective cooling elements, having parts extending downwardly to apoint near the bottom of said compartment and other parts extendingupwardly from the lowest parts thereof to polnts near the top of saidcom artment.

In testlmony whereof, I aifix my signature hereto.

. BURT H. WESTON ssf

